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Abstract MoS2 has attracted intense interest in many applications. Natural MoS2 and field-effect transistors made of it generally exhibit n-type characteristics, but its origin is unknown. Herein, we show that C is the origin of the universal n-type doping of natural MoS2. Photoemission spectroscopies reveal that while many MoS2 samples with C detected are n-type, some without C exhibit p-type characteristics. The C-free, p-type MoS2 changes to n-type over time with the concurrent appearance of C that is out-diffused from bulk, indicating that C induces the n-type doping. The C-origin is verified by C-deposition and supported by theoretical calculations. This carbon appears as nanometer-scale defects frequently observed in scanning tunneling microscopy. In addition, we propose, based on the calculations, that S vacancies are responsible for the p-type characteristics, which contrasts with the widespread belief. This work provides new perspectives on MoS2 doping and presents a new direction for fabricating reliable MoS2 devices.

The advancement of new tools in the field of control systems is a contemporary development. This work introduces the utilization of Type-3 fuzzy logic, a relatively recent concept that has been applied across various disciplines. In our case, a Type-3 fuzzy system is designed to enhance the optimization of parameters within the harmony search algorithm, specifically tailored for a control problem. Through a series of experiments, the efficacy of this novel Type-3 fuzzy logic tool is put to the test. Previous studies have primarily explored Type-1 and Type-2 fuzzy logic. To assess the performance of this new Type-3 fuzzy logic tool, a comparative analysis of results is conducted using statistical testing. The introduction of Type-3 fuzzy logic in the control domain represents a novel and innovative approach. This approach extends beyond the conventional Type-1 and Type-2 fuzzy logic, showcasing the dynamic evolution in the field. Results obtained through experimentation are analyzed, and statistical tests are employed to determine whether the Type-3 fuzzy logic tool yields superior outcomes compared to its predecessors. By doing so, this study contributes to the growing body of research that explores the potential benefits of Type-3 fuzzy logic and its application in control systems, offering new perspectives and opportunities for further advancements in the field. We have to mention that the utilization of Type-3 fuzzy logic in enhancing metaheuristics is a relatively new trend, and in this work, this research has extended this to the realm of harmony search. In addition, the application of the optimal design of the ball-and-beam fuzzy controllers has not been previously carried out with the Type-3 fuzzy harmony search algorithm, which is the novelty of this study.

In this study, we established a coculture model comprising human neuroblastoma SH-SY5Y cells and induced pluripotent stem cell-derived astrocytes, faithfully replicating the human brain environment for in vitro neurotoxicity assessment. We optimized the cell differentiation duration and cell ratios to obtain images conducive to neurite outgrowth evaluation. Subsequently, the neurotoxic effects in the coculture and monoculture of SH-SY5Y cells were confirmed using neurotoxic agents such as acrylamide (ACR) and hydrogen peroxide (H2O2). Disparities in the neurotoxic impacts of ACR and H2O2 within the coculture were mirrored in the expression of genes associated with early neuronal injury. Notably, the reduction in neurite outgrowth induced by neurotoxic agents revealed the coculture's lower sensitivity compared to monocultures. Furthermore, the coculture system exhibited distinct effects of test agents on nerve damage and manifested protective influences on nerve cells. The proposed methodology holds promise for large-scale chemical neurotoxicity screening through neurite change measurements. This in vitro coculture model, accounting for cell interactions, emerges as a valuable tool in toxicity testing, offering insights into the potential effects of chemicals within the human body.

When used as an image processing method, convolutional neural networks (CNNs) cannot verify conditions that can achieve high performance; however, they show sufficiently high performance and are used in various fields. The architecture of a CNN and various parameters determine its performance, and it is impossible to verify the number of all cases that determine the performance of the CNN. Therefore, well-known CNN models are generally used. Recently, various methods for adjusting the parameters of CNNs or generating CNN architectures have been studied in various ways. Methods using metaheuristic algorithms often focus on parameter tuning, or the use of simple hierarchical architectures. This paper proposes a method to create a CNN model with a complex CNN architecture that can be applied to different datasets using the harmony search (HS) algorithm from among metaheuristic algorithms. This study aimed to generate a CNN architecture using fewer computing resources and to verify the results. To make the CNN model in units of cells, the internal and hierarchical architecture of the cell was created based on the learning of the CIFAR image dataset through HS and the performance of the created CNN model was tested by applying it to the classification of a damaged sewer pipe image dataset. The 10-GPU-day computed result showed that the accuracy of classifying the damaged sewers was at least 5% higher than that of VGGNet, the highest among the existing CNN models. Keywords: convolutional neural network; auto machine learning; metaheuristic algorithm; harmony search algorithm; heuristic algorithm, optimization, artificial neural network, image classification.

The genotoxicity, development toxicity, carcinogenicity, and acute or chronic toxic effects of glutaraldehyde (GA), particularly during occupational exposure through its use as a fixative, disinfectant, and preservative, are well-documented but its effects on neurotoxicity have not been investigated. We performed in vitro and in vivo studies to examine the developmental neurotoxicity (DNT) of GA. Neurite outgrowth was examined in an in vitro co-culture model consisting of SH-SY5Y human neuroblastoma cells and human astrocytes. Cell Counting Kit-8, lactate dehydrogenase assay, and high-content screening revealed that GA significantly inhibited neurite outgrowth at non-cytotoxic concentration. Further studies showed that GA upregulated the mRNA expression of the astrocyte markers GFAP and S100β and downregulated the expression of the neurodevelopmental genes Nestin, βIII-tubulin, GAP43, and MAP2. Furthermore, in vivo zebrafish embryo toxicity tests explored the effects of GA on neural morphogenesis. GA adversely affected the early development of zebrafish embryos, resulting in decreased survival, irregular hatching, and reduced heart rate in a time- and concentration-dependent manner. Furthermore, the width of the brain and spinal cord was reduced, and the myelination of Schwann cells and oligodendrocytes was decreased by GA in transgenic zebrafish lines. These data suggest that GAs have potential DNT in vitro and in vivo, highlighting the need for caution regarding the neurotoxicity of GA.

Low-temperature Cu-Cu bonding technology plays a key role in high-density and high-performance 3D interconnects. Despite the advantages of good electrical and thermal conductivity and the potential for fine pitch patterns, Cu bonding is vulnerable to oxidation and the high temperature of the bonding process. In this study, chip-level Cu bonding using an Ag nanofilm at 150 °C and 180 °C was studied in air, and the effect of the Ag nanofilm was investigated. A 15-nm Ag nanofilm prevented Cu oxidation prior to the Cu bonding process in air. In the bonding process, Cu diffused rapidly to the bonding interface and pure Cu-Cu bonding occurred. However, some Ag was observed at the bonding interface due to the short bonding time of 30 min in the absence of annealing. The shear strength of the Cu/Ag-Ag/Cu bonding interface was measured to be about 23.27 MPa, with some Ag remaining at the interface. This study demonstrated the good bonding quality of Cu bonding using an Ag nanofilm at 150 °C.

Despite previous research efforts on identifying the risk and protective factors of problematic Internet use (PIU), the specific mechanism among these factors are largely unknown. Thus, the present study examined the effect of adolescents' social relationships on their PIU, as well as the effect of self-esteem as a mediator and the effect of self-control as a moderator. Survey data from 750 South Korean middle and high school students in Seoul and Gyeonggi areas were analyzed using structural equation modeling. The results are as follows. First, PIU is significantly associated with relationship with peers and with mother. Second, self-esteem did not mediate the effect of communication with mother on PIU, but was found to partially mediate the effect of peer relationship on PIU. Third, adolescents' self-control significantly moderated the indirect effect of peer relationship on PIU via self-esteem. Through detailed analyses, this study identified self-esteem as a mediator and self-control as a moderator in the relationship between social relationships and PIU. Implications of these results for understanding the relationship among social relationships, self-esteem, self-control, and PIU are discussed. [ABSTRACT FROM AUTHOR]

The article highlights that Transition metal dichalcogenides representative twodimensional van der Waals semiconducting materials, have gained substantial attention because of their attractive material properties, including their ultrathin 2D nature with superior electronic and optoelectronic properties, making them a strong contender for emerging electronics applications. It also mentions the mechanistic investigation of the remote doping method promotes the charge transfer strategy.